Silverstein J T, Bondareva V M, Leonard J B, Plisetskaya E M
USDA, ARS, Catfish Genetics Research Unit, Thad Cochran National Warmwater Aquaculture Center, 38776, Stoneville, MS, USA.
Comp Biochem Physiol B Biochem Mol Biol. 2001 Jun;129(2-3):623-31. doi: 10.1016/s1096-4959(01)00357-8.
Glucagon-like peptide 1 is a compound known to cause reduced food intake in mammals, though its action on feed intake in fish is unknown. The clear differences in the effects of GLP-1 on mammalian and teleostean glucose homeostasis suggest that we cannot assume a similar action of GLP-1 on feeding in mammals and fish. In this study the effects and specificity of centrally administered GLP-1 on feed intake were examined. It was demonstrated that intracerebroventricular (ICV) injection of glucagon-like peptide 1 (GLP-1) in the channel catfish (Ictalurus punctatus) is a potent inhibitor of feed intake with a dose of 0.25 ng g(-1) body wt. reducing feed intake by 50%. The weak response to intraperitoneal (i.p.) and intravenous (i.v.) injection treatments with GLP-1 suggests the major effects on feed intake are centrally mediated. GLP-1 action on feed intake was not antagonized by ICV injection of exendin(9-39). Immunoneutralization of GLP-1 by ICV injection of antisalmon GLP-1 antisera did not affect feed intake over 48 h, while ICV injection of GLP-1 at a dose of 30 ng g(-1) body wt. reduced feed intake for over 20 h. Additionally, there is some evidence that GLP-1 caused gastric evacuation. We conclude that GLP-1 is a potent inhibitor of feeding in fish, but its involvement in feed intake regulation under physiological conditions remains to be clarified.
胰高血糖素样肽1是一种已知可使哺乳动物食物摄入量减少的化合物，但其对鱼类采食量的作用尚不清楚。胰高血糖素样肽1对哺乳动物和硬骨鱼葡萄糖稳态的影响存在明显差异，这表明我们不能假定其对哺乳动物和鱼类摄食的作用相似。在本研究中，检测了脑内注射胰高血糖素样肽1对采食量的影响和特异性。结果表明，在斑点叉尾鮰（Ictalurus punctatus）脑室内（ICV）注射胰高血糖素样肽1（GLP-1）是采食量的有效抑制剂，剂量为0.25 ng g(-1)体重时可使采食量减少50%。腹腔内（i.p.）和静脉内（i.v.）注射GLP-1的反应较弱，表明其对采食量的主要影响是通过中枢介导的。脑室内注射艾塞那肽（9-39）并未拮抗GLP-1对采食量的作用。脑室内注射抗鲑鱼GLP-1抗血清对GLP-1进行免疫中和，在48小时内未影响采食量，而脑室内注射剂量为30 ng g(-1)体重的GLP-1可使采食量减少超过20小时。此外，有证据表明GLP-1可导致胃排空。我们得出结论，GLP-1是鱼类摄食的有效抑制剂，但其在生理条件下参与采食量调节的情况仍有待阐明。
